A smart phone is an intelligent mobile terminal incorporating functions of Personal Digital Assistant (PDA) and enabling the user to browse web pages and to send/receive e-mails. The smart phone can provide functions in addition to voice communication and facilitate provision of value-added services by telecommunication operators. In implementing these functions, the smart phone adopts an architecture in which an application processor and a communication processor are incorporated and the communication processor serves as a peripheral device of the application processor. Accordingly, functions like playing audio/video, reading and processing documents are performed by the application processor, and the communication processor provides the application processor with communication paths to implement communication functions. Therefore, the smart phone can operate either in an operation mode in which the application processor and the communication processor cooperate or in an operation mode in which only the application processor operates. In this way, users' demands on both mobile computing capability and communication can be satisfied.
FIG. 1 is a schematic diagram illustrating the architecture of an existing smart mobile terminal. The smart mobile terminal based on this architecture is designed to have an application processor (AP) as its master device. In addition, an storage, a USB interface for connecting a keyboard and a mouse, a display device (a LCD with T/P), an audio device and other peripheral devices (such as WiFi/BT/GPS) are each connected with the AP via an Input/Output (I/O) interface. The communication processor (CP) is also connected, via the I/O interface, with the AP as its peripheral device. It can be seen from the above architecture of the smart mobile terminal that, in the conventional techniques, the CP is configured as a peripheral device of the AP and thus can only operate in an operation state at the same time as the AP, i.e., it cannot operate alone and independently. The power consumption for the AP is much higher than that for the CP. Also, with the increasing computing/processing capability of the CP, when the smart mobile terminal only needs to perform communication functions (i.e., only the CP functions are required), it may result in great redundant power consumption, because the AP has to be started up as the master device prior to using the CP functions according to the existing architecture.